2010 GMC TERRAIN Owner's Manual

Vehicle Care 9-63
The Uniform Tire Quality
Grading (UTQG) system does
not apply to deep tread,
winter-type snow tires,
space-saver, or temporary use
spare tires, tires with nominal
rim diameters of 10 to 12 inches
(25 to 30 cm), or to some
limited-production tires.
While the tires available on
General Motors passenger cars
and light trucks may vary with
respect to these grades, they
must also conform to federal
safety requirements and
additional General Motors Tire
Performance Criteria (TPC)
standards.
All Passenger Car Tires Must
Conform to Federal Safety
Requirements In Addition To
These Grades.Treadwear
The treadwear grade is a
comparative rating based on the
wear rate of the tire when tested
under controlled conditions on a
specified government test
course. For example, a tire
graded 150 would wear one and
a half (1½) times as well on the
government course as a tire
graded 100. The relative
performance of tires depends
upon the actual conditions of
their use, however, and may
depart significantly from the
norm due to variations in
driving habits, service practices
and differences in road
characteristics and climate.
Traction
–AA, A, B, C
The traction grades, from
highest to lowest, are AA, A, B,
and C. Those grades represent
the tire's ability to stop on wet
pavement as measured under
controlled conditions on
specified government test
surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
Warning: The traction grade
assigned to this tire is based on
straight-ahead braking traction
tests, and does not include
acceleration, cornering,
hydroplaning, or peak traction
characteristics.

9-64 Vehicle Care
Temperature–A, B, C
The temperature grades are A
(the highest), B, and C,
representing the tire's resistance
to the generation of heat and
its ability to dissipate heat
when tested under controlled
conditions on a specified indoor
laboratory test wheel. Sustained
high temperature can cause the
material of the tire to degenerate
and reduce tire life, and
excessive temperature can
lead to sudden tire failure. The
grade C corresponds to a level of performance which all
passenger car tires must meet
under the Federal Motor Safety
Standard No. 109. Grades B and
A represent higher levels of
performance on the laboratory
test wheel than the minimum
required by law. Warning: The
temperature grade for this tire is
established for a tire that is
properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.Wheel Alignment and Tire
Balance
The tires and wheels on the vehicle
were aligned and balanced carefully
at the factory to give the longest tire
life and best overall performance.
Adjustments to wheel alignment and
tire balancing will not be necessary
on a regular basis. However, if there
is unusual tire wear or the vehicle
pulls to one side or the other, the
alignment should be checked. If the
vehicle vibrates when driving on a
smooth road, the tires and wheels
might need to be rebalanced. See
your dealer/retailer for proper
diagnosis.

Vehicle Care 9-65
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or
corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts, and
wheel nuts should be replaced.
If the wheel leaks air, replace it
(except some aluminum wheels,
which can sometimes be repaired).
See your dealer/retailer if any of
these conditions exist.
Your dealer/retailer will know the
kind of wheel you need.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset, and be
mounted the same way as the
one it replaces.If you need to replace any of the
wheels, wheel bolts, wheel nuts,
or Tire Pressure Monitor System
(TPMS) sensors, replace them only
with new GM original equipment
parts. This way, you will be sure to
have the right wheel, wheel bolts,
wheel nuts, and TPMS sensors for
the vehicle.
{WARNING
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts on your vehicle can be
dangerous. It could affect the
braking and handling of your
vehicle, make your tires lose air
and make you lose control. You
could have a collision in which
you or others could be injured.
Always use the correct wheel,
wheel bolts, and wheel nuts for
replacement.Notice:
The wrong wheel can
also cause problems with bearing
life, brake cooling, speedometer
or odometer calibration,
headlamp aim, bumper height,
vehicle ground clearance, and
tire or tire chain clearance to the
body and chassis.
See If a Tire Goes Flat
on
page 9‑67for more information.

9-66 Vehicle Care
Used Replacement Wheels
{WARNING
Putting a used wheel on the
vehicle is dangerous. You cannot
know how it has been used or
how far it has been driven.
It could fail suddenly and cause a
crash. If you have to replace a
wheel, use a new GM original
equipment wheel.
Tire Chains
{WARNING
Do not use tire chains. There is
not enough clearance. Tire chains
used on a vehicle without the
proper amount of clearance can
cause damage to the brakes,
suspension or other vehicle parts.
The area damaged by the tire
chains could cause you to lose
control of the vehicle and you or
others may be injured in a crash.(Continued)
WARNING (Continued)
Use another type of traction
device only if its manufacturer
recommends it for use on the
vehicle and tire size combination
and road conditions. Follow that
manufacturer's instructions. To
help avoid damage to the vehicle,
drive slowly, readjust or remove
the device if it is contacting the
vehicle, and do not spin the
vehicle's wheels. If you do find
traction devices that will fit, install
them on the front tires.

Vehicle Care 9-67
If a Tire Goes Flat
It is unusual for a tire to blowout
while you are driving, especially if
you maintain your vehicle's tires
properly. If air goes out of a tire, it is
much more likely to leak out slowly.
But if you should ever have a
blowout, here are a few tips about
what to expect and what to do:
If a front tire fails, the flat tire
creates a drag that pulls the vehicle
toward that side. Take your foot off
the accelerator pedal and grip the
steering wheel firmly. Steer tomaintain lane position, and then
gently brake to a stop well out of the
traffic lane.
A rear blowout, particularly on a
curve, acts much like a skid and
may require the same correction
you would use in a skid. In any rear
blowout remove your foot from the
accelerator pedal. Get the vehicle
under control by steering the way
you want the vehicle to go. It may
be very bumpy and noisy, but you
can still steer. Gently brake to a
stop, well off the road if possible.{WARNING
Lifting a vehicle and getting
under it to do maintenance or
repairs is dangerous without the
appropriate safety equipment and
training. If a jack is provided with
the vehicle, it is designed only for
changing a flat tire. If it is used for
anything else, you or others could
be badly injured or killed if the
vehicle slips off the jack. If a jack
is provided with the vehicle, only
use it for changing a flat tire.

9-68 Vehicle Care
If a tire goes flat, avoid further tire
and wheel damage by driving slowly
to a level place. Turn on the hazard
warning flashers. SeeHazard
Warning Flashers on page 5‑3.
{WARNING
Changing a tire can be
dangerous. The vehicle can slip
off the jack and roll over or fall on
you or other people. You and they
could be badly injured or even
killed. Find a level place to
change your tire. To help prevent
the vehicle from moving:
1. Set the parking brake firmly.
2. Put an automatic transmission shift lever in
P (Park), or shift a manual
transmission to 1 (First) or
R (Reverse).
(Continued)
WARNING (Continued)
3. Turn off the engine and donot restart while the vehicle
is raised.
4. Do not allow passengers to remain in the vehicle.
To be certain the vehicle will not
move, put blocks at the front and
rear of the tire farthest away from
the one being changed. That
would be the tire on the other
side, at the opposite end of the
vehicle.
When the vehicle has a flat tire (B),
use the following example as a
guide to assist you in the placement
of wheel blocks (A).
A. Wheel Block
B. Flat Tire
The following information explains
how to repair or change a tire.

Vehicle Care 9-69
Tire Changing
Removing the Spare Tire and
Tools
To access the spare tire and tools:
1. Open the liftgate. SeeLiftgate
(Manual)
on page 1‑8or
Liftgate (Power) on page 1‑9.
2. Lift the load floor up.
3. Remove the extension (A), wheel wrench (B) and jack (C).
Place the tools next to the tire
being changed.
4. Turn the retainer nutcounterclockwise and remove
the spare tire.
5. Place the spare tire next to the tire being changed.
Removing the Flat Tire and
Installing the Spare Tire
1. Do a safety check beforeproceeding. See If a Tire Goes
Flat
on page 9‑67for more
information.
2. For vehicles with wheel nut caps, turn the wheel wrench
counterclockwise to loosen and
remove them.
Do not try to remove plastic caps
from the cover or center cap.
3. For vehicles with a wheel cover or center cap, pull the cover or
center cap away from the wheel
to remove it. Store the wheel
cover in the cargo area until you
have the flat tire repaired or
replaced.

9-70 Vehicle Care
4. Turn the wheel wrenchcounterclockwise to loosen all
the wheel nuts, but do not
remove them yet.
5. Place the jack near the flat tire. Notice:
Make sure that the jack
lift head is in the correct position
or you may damage your vehicle.
The repairs would not be covered
by your warranty.
Front
Rear
6. Position the jack lift head at the jack location nearest the flat tire.
The location is indicated by a
mark on the bottom edge of the
front and rear door plastic
molding. The jack must not be
used in any other position.